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A seven month-old baby in Belgium died from malnutrition after his parents put him on an alternative gluten-free diet despite no actual medical diagnosis or recommendation. The child weighed only 9 pounds, about half the size of an average child his age, and was extremely dehydrated. The story brings to light just how dangerous alternative diets can be for very young children.

The baby, identified only as “Lucas” by The Daily Mail, was raised on a gluten-free diet consisting of quinoa milk, rice milk, oat milk, and other alternative milk products. Upon noticing their child’s diminishing health—the boy was described as extremely thin and “gasping for air”—his parents, named only as Peter S and Sandrina V, took him to visit a homeopathic doctor. The homeopath however immediately sent the family to a hospital.

Unfortunately, the young boy was announced dead on arrival at the hospital, with extreme malnutrition cited as the likely cause. An autopsy revealed that the child’s stomach was nearly completely empty and he was very dehydrated as well. The child died in June 2014, but his parent’s trial still continues.

According to the public prosecutor in the family’s hometown in Belgium, the boy’s gluten allergies were never confirmed by a doctor, nor was his extreme diet.

“The parents determined their own diagnosis that their child was gluten intolerant and had a lactose allergy,” explained the public defender, The Independent reported.“Not a single doctor had a dossier about Lucas and child protection services did not know about them.”

The parents defend their health decisions regarding their son, stating that he never seemed ill or unusual, and his weight had always been up and down. However, according to Parents.com, at around 7 months of age, babies should be gaining an average of two pounds a month, and parents should consult a doctors if their child gains less than this. The parents lawyer, Karine Van Meirvenne explained that the parents thought their child’s strange weight gain was due to an eating problem, not dietary issue, as he often got cramps when fed with a bottle.

“We never went with Lucas to a doctor because we never noticed anything unusual,” said the father, with the child’s mother adding “Sometimes he gained a little weight, sometimes he lost a little. We never wished for the death of our son,” The Independent reported.

While it remains unclear as to whether or not the child had any specific food allergies, new research has shown that gluten free diets could pose a risk for those without celiac disease. For example, one of the main health risks of this diet for those without medical needs is malnutrition. According to The Mayo Clinic, gluten-free diets tend to be low in iron, calcium, fiber thiamin, riboflavin, niacin, and folate—all important nutrients and vitamins for a balanced diet.

Child doctor Elisabeth De Greef from the University Hospital of Brussels, told The Daily Mail that feeding a young child only gluten-free without medication recommendation is extremely dangerous.

“These kinds of milk, which you can buy in a supermarket, do not contain the necessary proteins, minerals and vitamins,” explained De Greef. “They are not adjusted to infants and thus unsuitable.”